CN113691129A - Voltage conversion method, device and conversion circuit based on wide input voltage - Google Patents
Voltage conversion method, device and conversion circuit based on wide input voltage Download PDFInfo
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- CN113691129A CN113691129A CN202110904707.5A CN202110904707A CN113691129A CN 113691129 A CN113691129 A CN 113691129A CN 202110904707 A CN202110904707 A CN 202110904707A CN 113691129 A CN113691129 A CN 113691129A
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- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
- H02M3/00—Conversion of dc power input into dc power output
- H02M3/02—Conversion of dc power input into dc power output without intermediate conversion into ac
- H02M3/04—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters
- H02M3/10—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode
- H02M3/145—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal
- H02M3/155—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only
- H02M3/156—Conversion of dc power input into dc power output without intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode using devices of a triode or transistor type requiring continuous application of a control signal using semiconductor devices only with automatic control of output voltage or current, e.g. switching regulators
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F13/00—Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units
- G06F13/38—Information transfer, e.g. on bus
- G06F13/40—Bus structure
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- G06F13/4022—Coupling between buses using switching circuits, e.g. switching matrix, connection or expansion network
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- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
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Abstract
The application relates to a voltage conversion method, a voltage conversion device and a voltage conversion circuit based on wide voltage of input voltage. The method comprises the steps of obtaining an input voltage; when the input voltage is lower than the preset switching voltage, closing a switch voltage reduction circuit, and conducting a field effect transistor circuit connected with the switch voltage reduction circuit in parallel; the resistance value of the field effect transistor circuit is smaller than that of the switch voltage reduction circuit. When the input voltage is less than the switching voltage, the switch voltage reduction circuit is closed, the field effect transistor circuit is conducted, and the input voltage is output after passing through the field effect transistor circuit. Because the resistance value of the field effect transistor circuit is smaller than that of the switch voltage reduction circuit, the generated voltage drop is small, and the output voltage is convenient to be stabilized in the voltage range of the product requirement. The power supply has the effects of long service life, stable function, high power conversion efficiency, environmental protection and low cost.
Description
Technical Field
The present invention relates to the field of voltage conversion, and in particular, to a voltage conversion method, device and conversion circuit based on wide input voltage.
Background
The input voltage of some products on the market is variable, and the voltage required by a certain circuit in the products is fixed. In order to ensure the normal application of the product, a switching buck chip is generally used to buck the input voltage to the required voltage of the product.
For example, for a Type-C interface docking station widely used by people at present, an uplink interface of the docking station can be connected with an input voltage of 5V-20V, but a downlink interface often needs an output voltage of 5V. For this case, one would choose to add a switching buck chip in the docking station. No matter what the value of the input voltage is, the voltage is reduced to 5V by the switch voltage reduction chip and is output to the downlink interface.
In addition, this is also often the case for USB hubs, smart phones, computers, data cameras and external power supplies. The voltage input end can input 5V, 10V, 15V or 20V, but the voltage required by the product is 5V. In order to avoid damaging the product due to overhigh input voltage, the input voltage is required to be reduced.
The switching buck chip in the related art mainly includes two types. One uses a P-channel fet for the output upper transistor; the advantage of this type of switching buck chip is that it supports a 100% switching duty cycle, with the output voltage being equal to the input voltage when the output is unloaded. The disadvantages of high internal resistance and high cost; and the larger internal resistance not only reduces the power conversion efficiency, but also reduces the output voltage. When the input voltage is 5V, the output voltage is less than 5V, which easily causes the function abnormality of the product.
The other is that an output upper tube uses an N-channel field effect tube; the switching step-down chip has the advantages of low cost and low internal resistance. The disadvantage is that the switching duty ratio can not reach 100%, even when the output is no-load, a certain voltage drop can be generated due to the switching duty ratio; when the internal resistance of the switching step-down chip is added, the output voltage is further reduced, so that when the input voltage is 5V, the output voltage is less than 5V, and the function of a product is easy to be abnormal.
In view of the above-mentioned related technologies, the inventor finds that when the input voltage of the product is in a certain range, that is, the input voltage of the product is a wide voltage, if the lowest input voltage value of the wide voltage is equal to the voltage value required by the product, the switching step-down chip may cause the lowest input voltage value to further drop, and the voltage actually obtained by the product is less than the required voltage, which may easily damage the product or cause the function of the product to be abnormal.
Disclosure of Invention
In order to help ensure the normal use of a product when the lowest input voltage value of the wide voltage is equal to the voltage value required by the product, the invention provides a voltage conversion method, a voltage conversion device and a voltage conversion circuit based on the input voltage as the wide voltage.
In a first aspect, the voltage conversion method based on wide input voltage provided by the present application adopts the following technical solutions:
a voltage conversion method based on wide voltage of input voltage comprises the following steps:
acquiring an input voltage;
when the input voltage is lower than the preset switching voltage, closing a switch voltage reduction circuit, and conducting a field effect transistor circuit connected with the switch voltage reduction circuit in parallel; the resistance value of the field effect transistor circuit is smaller than that of the switch voltage reduction circuit.
By adopting the technical scheme, when the input voltage is close to the lowest input voltage value of the wide voltage, namely the input voltage is smaller than the switching voltage, the field effect transistor circuit is switched on, and the switch voltage reduction circuit is switched off. Because the field effect transistor circuit is connected with the switch voltage reduction circuit in parallel, the output of the input voltage is not influenced. The resistance value of the field effect transistor circuit is smaller than that of the switch voltage reduction circuit, so that the voltage reduction degree is reduced, the voltage actually obtained by the product meets the required voltage requirement, and the product is not easy to damage or the function of the product is abnormal.
Optionally, the step of calculating the switching voltage includes:
obtaining the fluctuation range ratio of the rated output voltage and the rated output voltage;
obtaining a switching voltage based on C = X + X Y + N;
wherein C is a switching voltage; x is rated output voltage; y is the fluctuation range ratio of the rated output voltage; n is an extension value.
By adopting the technical scheme, the fluctuation range ratio of the rated output voltage is the requirement of the product output voltage, for example, the output voltage required by the product is 5V, namely the rated output voltage of the product is 5V, and the fluctuation range ratio of the rated output voltage is 5%. The actual output voltage of the product is proved to be in accordance with the requirement between 4.75 and 5.25V, and the product is not easy to damage or cause the function abnormity of the product. And the switching voltage is obtained based on the formula C = X + X × Y + N, where X =5 and Y =5% are substituted into the formula, taking 5V and 5% as examples, resulting in C =5.25+ N. Namely, when the input voltage is less than 5.25+ N, the input voltage is directly output through the field effect transistor circuit, so that the voltage drop is reduced, and the output voltage requirement of a product is met. The expansion value N is used to compensate the effect of voltage drop generated by the fet circuit, for example, when the input voltage is 5.25V, the output voltage of the fet circuit is 5.20V, which generates a voltage drop of 0.5V. Enabling the expansion value N =0.5, namely when the input voltage is less than 5.3V, outputting the voltage by using a field effect transistor circuit, wherein the output voltage is convenient to meet the product requirement, and the product is not easy to damage or the product is abnormal in function; when the input voltage is greater than or equal to 5.3V, the switch voltage reduction circuit is used for outputting the voltage, the voltage drop amplitude of the output voltage is increased, the output voltage is convenient to fall into the requirement range of a product, and the product is not easy to damage or the function of the product is abnormal.
Optionally, the step of calculating the switching voltage includes:
obtaining rated output voltage and the maximum switching duty ratio of a switching step-down circuit;
obtaining a switching voltage based on C = X + (X-X K) + M;
wherein C is a switching voltage; x is rated output voltage; k is the maximum switching duty ratio of the switching voltage reduction circuit; m is a compensation value.
By adopting the above technical solution, the output voltage = input voltage and switching duty ratio, for example, when the input voltage is 5V, the switching duty ratio is 80%, and the compensation value M =0.1V, the output voltage is 4V. Obtaining a voltage drop value of the switching voltage drop circuit generated by the switching duty ratio when the input voltage is equal to the rated output voltage of the product through X-X K; for example, when X =5V and K =0.9, the voltage drop value of the switching step-down circuit due to the switching duty ratio is 0.5V. The rated output voltage of the used product is added with a voltage drop value to obtain a switching voltage, namely 5.6V. When the input voltage is greater than or equal to 5.6V, the switch voltage reduction circuit is used for outputting the voltage, and the internal resistance of the switch voltage reduction circuit is higher, so that a certain voltage drop is generated, the output voltage value is further reduced, and the input voltage value greater than 5.6V is reduced to the voltage value range required by the product. And when the input voltage is less than 5.6V, the field effect transistor circuit is used for outputting the voltage, so that the voltage drop degree is reduced, and the output voltage meets the product requirement. The product is not easy to be damaged or abnormal in function because the output voltage is lower than the required voltage.
Optionally, the specific steps of turning off the switching step-down circuit and turning on the fet circuit connected in parallel to the switching step-down circuit include:
the detection module transmits a first switching instruction to the driving module;
the driving module transmits a transfer signal to the switch control module and outputs a conducting signal to the field effect transistor circuit based on a first switching instruction;
the switch control module transmits a turn-off signal to the switch voltage reduction circuit based on the transit signal.
By adopting the technical scheme, when the input voltage is less than the switching voltage, the detection module transmits a first switching instruction to the driving module; the driving module transmits corresponding signals to the switch control module and the field effect transistor circuit respectively based on the first switching instruction, and controls the field effect transistor circuit to be conducted; the switch control module controls the switch voltage reduction circuit to be closed. The field effect transistor circuit and the switch voltage reduction circuit are controlled through different modules, and the control is simple and easy.
Optionally, the specific steps of turning off the switching step-down circuit and turning on the fet circuit connected in parallel to the switching step-down circuit include:
the detection module transmits a second switching instruction to the driving module and transmits a third switching instruction to the switch control module;
the driving module outputs a conducting signal to the field effect transistor circuit based on a second switching instruction;
the switch control module outputs a turn-off signal to the switch voltage reduction circuit based on a third switching instruction.
By adopting the technical scheme, the detection module transmits the switching instruction to the driving module and the switch control module respectively, and the driving module and the switch control module respectively control the correspondingly connected circuits, so that the circuit is simple and easy to control.
Optionally, the specific steps of turning off the switching step-down circuit and turning on the fet circuit connected in parallel to the switching step-down circuit include:
the detection module transmits a fourth switching instruction to the driving module;
and the driving module outputs a closing signal to the switch voltage reduction circuit and outputs a conducting signal to the field effect transistor circuit based on a fourth switching instruction.
By adopting the technical scheme, the driving module outputs different signals to the switch voltage reduction circuit and the field effect transistor circuit based on the fourth switching instruction, so that the switch voltage reduction circuit is closed, the field effect transistor circuit is switched on, the control of the two circuits is realized only through one module, and the structure is simple.
In a second aspect, the present application provides a voltage conversion apparatus based on a wide input voltage, which adopts the following technical solution:
a voltage conversion device based on wide voltage of input voltage comprises a memory and a processor, wherein the memory stores a voltage conversion program based on wide voltage of input voltage; the processor is configured to perform the steps of any of the above methods when running a voltage conversion program based on an input voltage being a wide voltage.
By adopting the technical scheme, when the input voltage is less than the switching voltage, the switching voltage reduction circuit is closed, the field effect transistor circuit is switched on, and the input voltage is output after passing through the field effect transistor circuit. Because the resistance value of the field effect transistor circuit is smaller than that of the switch voltage reduction circuit, the generated voltage drop is small, the output voltage is convenient to be stabilized in the voltage range of the product requirement, and the product is not easy to damage or the function of the product is abnormal.
In a third aspect, the present application provides a voltage conversion circuit based on a wide voltage of an input voltage, which adopts the following technical solution:
a voltage conversion circuit based on wide voltage of input voltage comprises a switch voltage reduction circuit, a field effect tube circuit and a control circuit, wherein the resistance value of the field effect tube circuit is smaller than that of the switch voltage reduction circuit;
the voltage input end of the field effect transistor circuit is connected with the voltage input end of the switch voltage reduction circuit, and the voltage output end of the field effect transistor circuit is connected with the voltage output end of the switch voltage reduction circuit; the voltage input end of the control circuit is connected with the voltage input end of the switch voltage reduction circuit, and the output end of the control circuit is respectively connected with the control end of the switch voltage reduction circuit and the control end of the field effect transistor circuit;
the control circuit is used for obtaining input voltage, transmitting a closing signal to the control end of the switch voltage reduction circuit when the input voltage is smaller than preset switching voltage, and transmitting a conducting signal to the control end of the field effect transistor circuit.
By adopting the technical scheme, after the control circuit acquires the input voltage, whether the input voltage is smaller than the preset switching voltage is judged. If the voltage of the input voltage of the switch voltage reduction circuit is smaller than the preset voltage, corresponding control signals are respectively transmitted to the control end of the switch voltage reduction circuit and the control end of the field effect tube circuit, the switch voltage reduction circuit is closed, and the field effect tube circuit is conducted. Therefore, the input voltage can only be output after passing through the field effect transistor circuit; and because the resistance value of field effect transistor circuit is less than the resistance value of switch step-down circuit, therefore the input voltage passes through the voltage drop that field effect transistor circuit produced and is less than the voltage drop that produces through switch step-down circuit, is convenient for satisfy output voltage's demand to be convenient for satisfy the demand of product, make the product not fragile or the function is unusual.
Optionally, the switching voltage reduction circuit includes a switching voltage reduction chip U1; the voltage input end of the switch voltage-reducing chip U1 is connected with the voltage input end of the switch voltage-reducing circuit, and the voltage output end of the switch voltage-reducing chip U1 is connected with the voltage output end of the switch voltage-reducing circuit;
the field effect transistor circuit comprises a field effect transistor Q1; the voltage input end of the field effect transistor Q1 is connected with the voltage input end of the field effect transistor circuit, and the voltage output end of the field effect transistor Q1 is connected with the voltage output end of the field effect transistor circuit;
the control circuit comprises a detection module, a driving module and a switching step-down chip, wherein the detection module is used for acquiring the input voltage of the voltage input end of the switching step-down chip U1 and transmitting a first switching instruction to the driving module when the input voltage is smaller than a preset switching voltage;
the driving module is used for acquiring the first switching instruction transmitted by the detection module, and transmitting a conducting signal to the grid of the field-effect tube Q1 and a transfer signal to the switch control module based on the first switching instruction;
and the switch control module is used for receiving the transit signal transmitted by the driving module and transmitting a closing signal to the control end of the switch voltage reduction chip U1 based on the transit signal.
Through adopting above-mentioned technical scheme, be provided with other field effect transistor and inductance in the switch step-down chip U1, and the inner structure of switch step-down chip U1 is difficult for changing, and switch step-down chip U1's the biggest switch duty cycle and resistance value have all been fixed promptly. Therefore, when the switching buck chip U1 receives the lowest input voltage of the wide voltage, the voltage drop degree of the switching buck chip U1 is not easily adjusted, and the output voltage is easily lower than the minimum value of the voltage required by the product, so that the function of the product is abnormal. However, the field effect transistor Q1 in the field effect transistor circuit can be replaced at will, or a PMOS with a larger resistance value but a maximum switching duty ratio of 100% can be used; or the NMOS with smaller resistance value and low cost is used. In both PMOS and NMOS circuits, since no inductor is provided in the fet circuit, the resistance value is easily smaller than that of the switching step-down chip U1. Therefore, the voltage drop degree is convenient to control, and the output voltage is ensured to meet the product requirement. In addition, the field effect transistor circuit with the smaller resistance value has higher power conversion efficiency, is convenient for energy saving and is green and environment-friendly.
Optionally, the switching voltage reduction circuit includes a switching voltage reduction chip U1; the voltage input end of the switch voltage-reducing chip U1 is connected with the voltage input end of the switch voltage-reducing circuit, and the voltage output end of the switch voltage-reducing chip U1 is connected with the voltage output end of the switch voltage-reducing circuit;
the field effect transistor circuit comprises a field effect transistor Q1; the voltage input end of the field effect transistor Q1 is connected with the voltage input end of the field effect transistor circuit, and the voltage output end of the field effect transistor Q1 is connected with the voltage output end of the field effect transistor circuit;
the control circuit comprises a detection module, a driving module and a switch control module, wherein the detection module is used for acquiring the input voltage of the voltage input end of the switch voltage reduction chip U1, and transmitting a second switching instruction to the driving module and a third switching instruction to the switch control module when the input voltage is smaller than a preset switching voltage;
the driving module is used for acquiring a second switching instruction transmitted by the detection module and transmitting a conducting signal to the grid of the field-effect tube Q1 based on the second switching instruction;
and the switch control module is used for acquiring a third switching instruction transmitted by the detection module and transmitting a closing signal to the control end of the switch voltage reduction chip U1 based on the third switching instruction.
By adopting the technical scheme, the field effect transistor Q1 is controlled to be switched on and off by the driving module, and the switch voltage reduction chip U1 is controlled to be switched off and switched on by the switch control module. The two modules respectively control the field effect transistor Q1 and the switch voltage reduction chip U1, do not affect each other, are simple and easy to implement, and are beneficial to simplifying the complexity of the driving module and/or the switch control module.
In summary, when the input voltage is less than the switching voltage, the switching step-down circuit is turned off, and the fet circuit is turned on, so that the input voltage is output after passing through the fet circuit. Because the resistance value of the field effect transistor circuit is smaller than that of the switch voltage reduction circuit, the generated voltage drop is small, the output voltage is convenient to be stabilized in the voltage range of the product requirement, and the product is not easy to damage or the function of the product is abnormal.
Drawings
Fig. 1 is a flowchart of a voltage conversion method based on wide input voltage according to an embodiment of the present application.
Fig. 2 is a flowchart illustrating a calculation of a switching voltage in a voltage conversion method based on a wide input voltage according to an embodiment of the present application.
Fig. 3 is another flowchart of calculating a switching voltage in a voltage conversion method based on a wide input voltage according to an embodiment of the present application.
Fig. 4 is a flowchart of turning off the voltage step-down circuit and turning on the fet circuit in a voltage conversion method based on a wide input voltage according to an embodiment of the present application.
Fig. 5 is another flowchart of turning off the voltage step-down circuit and turning on the fet circuit in a voltage conversion method based on a wide input voltage according to an embodiment of the present application.
Fig. 6 is another flowchart of turning off the voltage step-down circuit and turning on the fet circuit in a voltage conversion method based on a wide input voltage according to an embodiment of the present application.
Fig. 7 is a block diagram of an overall structure of a voltage conversion circuit based on a wide-range input voltage according to an embodiment of the present application.
Fig. 8 is a block diagram of a voltage conversion circuit based on a wide input voltage according to an embodiment of the present application.
Fig. 9 is another block diagram of a voltage conversion circuit based on a wide input voltage according to an embodiment of the present application.
Description of reference numerals:
1. a switching voltage reduction circuit; 2. a field effect transistor circuit; 3. a control circuit; 31. a detection module; 32. a drive module; 33. and a switch control module.
Detailed Description
The embodiment of the application discloses a voltage conversion method based on wide voltage of input voltage. Referring to fig. 1, includes:
100. an input voltage is obtained.
The input voltage is a wide voltage, i.e. the input voltage is not a fixed value, and may be 5V, 10V, 12V, 15V, 18V or 20V. For example, when a mobile phone is charged by using different power adapters, the input voltage of the mobile phone is different, and may be 5V or 3.3V. For another example, when the docking station is used, the uplink interface of the docking station is connected with a computer, and the computer provides electric energy for the docking station; the input voltage transmitted to the docking station from different computers is also different, and may be 12V, 5V or 3.3V. It will be referred to as a wide voltage that the input voltage can vary within a certain range, similarly to the above case.
It should be noted that, although most products are suitable for wide voltage input, the voltage required by some products or the voltage required by a circuit in a product is fixed. For example, the input voltage of the docking station may be between 5V and 20V, but the voltage required to be supplied to a certain downstream interface is 5V, and at this time, the input voltage of the docking station needs to be reduced.
S200, judging whether the input voltage is smaller than a preset switching voltage or not.
And S300, when the input voltage is less than the switching voltage, closing the switch voltage reduction circuit 1, and conducting the field effect transistor circuit 2 connected with the switch voltage reduction circuit 1 in parallel.
S400, when the input voltage is larger than or equal to the switching voltage, the switching voltage reduction circuit 1 is closed, and the field effect transistor circuit 2 is cut off.
The resistance value of the field-effect transistor circuit 2 is smaller than the resistance value of the switching step-down circuit 1. The resistance value of the switching step-down circuit 1 refers to a resistance value connected in series between the voltage input end and the voltage output end of the switching step-down circuit 1.
As an embodiment, referring to fig. 2, the step of calculating the switching voltage includes:
s210, obtaining the rated output voltage and the fluctuation range ratio of the rated output voltage.
The rated output voltage refers to a rated operating voltage of a product or a rated output voltage of a product. For example, when a battery of a smart phone is charged by the smart phone, if the rated voltage required by the battery is 5V, the input voltage of the smart phone needs to be reduced to 5V, and the rated output voltage is 5V; for another example, if the USB interface of the docking station needs to provide a voltage of 5V for the connected USB disk, the docking station needs to provide an output voltage of 5V for the USB interface, and the rated output voltage is 5V.
The fluctuation range ratio of the rated output voltage refers to the voltage fluctuation ratio acceptable or specified by the product. For example, in the case of a smartphone, when the rated output voltage is 5V, the rated output voltage is specified to be not higher than 5.15V and not lower than 4.85V, and the fluctuation range ratio is 3%. For another example, for the USB interface of the docking station, the rated output voltage is 5V, and there may be 5% voltage fluctuation, i.e. the fluctuation range ratio of the rated output voltage is 5%.
And S220, obtaining a switching voltage based on C = X + X Y + N.
C is a switching voltage; x is rated output voltage; y is the fluctuation range ratio of the rated output voltage; n is an extension value. It should be noted that, no matter the input voltage passes through the switching step-down circuit 1 or the fet circuit 2, a certain voltage drop occurs. Therefore, N is set based on the voltage drop value generated by the fet circuit 2 when calculating the switching voltage. For example, fet circuit 2 may generate a voltage drop of 0.1V, and then N =0.1V or 0.12V. The expansion value N is set to increase the switching voltage, so that the voltage requirement of a product can be met after the input voltage is output through the field effect transistor circuit 2; the setting standard of the switching step-down circuit 1 can be lowered.
It is understood that if the rated output voltage X is 5V, the fluctuation range ratio Y of the rated output voltage is 5%. When the spread value N =0, the switching voltage is 5.25V. Then prove that when the input voltage is less than 5.25V, the field effect transistor circuit 2 is used to output voltage; when the input voltage is greater than or equal to 5.25V, the voltage is output using the switching step-down circuit 1. Since the lowest voltage L = X-X Y =4.75V that the product can accept, the switching step-down circuit 1 with the maximum voltage drop smaller than 0.5V must be found, otherwise, when the input voltage is equal to 5.25V, the output voltage is 4.75V, which is very likely to affect the stability of the product due to too low voltage.
But if the spread value N =0.1V, the switching voltage is 5.35V. When the input voltage is less than 5.35V, the field effect transistor circuit 2 is used for outputting voltage; when the input voltage is greater than or equal to 5.35V, the voltage is output using the switching step-down circuit 1. Because the lowest voltage L =4.75V that the product can accept, can find the switching step-down circuit 1 that the biggest voltage drop is less than 0.6V, reduced the setting standard of switching step-down circuit 1.
As another embodiment, referring to fig. 3, the calculating of the switching voltage includes:
and S230, acquiring the rated output voltage and the maximum switching duty ratio of the switching step-down circuit 1.
The switching duty ratio of the switching step-down circuit 1 refers to a ratio of time of outputting voltage to one period of the switching step-down circuit 1 in one period. For example, the period T =1s, the time of outputting the voltage in each period is 0.6s, and the switching duty ratio is 0.6; for another example, if the period T =1s and the time of outputting the voltage in each period is 1s, the switching duty ratio is 1. The maximum switching duty ratio is the maximum switching duty ratio that the switching step-down circuit 1 can achieve, and is limited by the field effect transistor used in the switching step-down circuit 1.
And S240, obtaining a switching voltage based on C = X + (X-X K) + M.
Wherein C is a switching voltage; x is rated output voltage; k is the maximum switching duty ratio of the switching step-down circuit 1; m is a compensation value. The minimum voltage drop value of the open-circuit voltage-drop circuit, i.e. X-X × K, can be obtained using the maximum switching duty cycle of the switched voltage-drop circuit 1. For example, when the rated output voltage X =5V and the maximum switching duty K =90% of the switching step-down circuit 1, the minimum step-down value of the switching step-down circuit 1 is 0.5V and the switching voltage C = 5.5V. That is, when the input voltage is greater than or equal to 5.5V, the input voltage is output through the switching step-down circuit 1. The actual output voltage is further reduced under the influence of the resistance value of the switching step-down circuit 1, and at this time, a compensation value M is set to compensate for further generated voltage drop, so that the output voltage is not easily smaller than the minimum voltage acceptable by a product, for example, M =0.1V or 0.12V.
Due to the setting of the compensation value M, the value of the switching voltage is increased, e.g. when M =0.1V, the switching voltage C changes from 5.5V to 5.6V. The increased switching voltage value can cause that when the input voltage is less than 5.6V, the light-on voltage reduction circuit is closed, and the field effect transistor circuit 2 is switched on. If the voltage drop of the fet circuit 2 is small, for example, only 0.3V, when the fluctuation range of the rated output voltage of the product is larger than Y =5%, the voltage actually obtained by the product is 5.3V, which is too high and is not within the voltage range acceptable by the product, i.e., no longer between 4.75V and 5.25V, and the product is easily damaged or the product functions abnormally. Therefore, the fet circuit 2 having a large resistance value can be selected at this time, which facilitates reduction in the setting standards of the fet. Further, since it is necessary to increase the resistance value of the field effect transistor circuit 2, the POMS type field effect transistor circuit 2 can be selected. The duty ratio of 100% is easily reached, the power conversion efficiency is improved, the energy is saved, and the environment is protected.
Referring to fig. 4, in an embodiment, the specific steps of turning off the switching step-down circuit 1 and turning on the fet circuit 2 connected in parallel to the switching step-down circuit 1 include:
s310, the detecting module 31 transmits a first switching instruction to the driving module 32.
The first switching instruction may be a voltage value, may be a digital signal, such as 0 or 1, and may be a computer instruction.
S320, the driving module 32 transmits the relay signal to the switch control module 33 and outputs the on signal to the fet circuit 2 based on the first switching instruction.
And S330, the switch control module 33 transmits a closing signal to the switch voltage reduction circuit 1 based on the transit signal.
For S320 and S330, it should be noted that: after the driving module 32 receives the first switching instruction, when the first switching instruction is a voltage, the driving module 32 amplifies the first switching instruction until the fet circuit 2 can be turned on.
Meanwhile, the driving module 32 may transmit the first switching command to the switch control module 33 as a relay signal, or may transmit the amplified voltage signal to the switch control module 33 as a relay signal. And enabling the switch control module 33 to transmit a closing signal to the switch voltage reduction circuit 1 based on the transit signal, and enabling the switch voltage reduction circuit 1 to be closed. It is understood that the switching control module 33 may step down the transfer signal, so as to control the switching step-down circuit 1 to be turned off. The analog-to-digital conversion can also be carried out on the intermediate transfer signal to control the switch voltage reduction circuit 1 to be closed. Specifically, the switch control module 33 is selected according to the structure of the switching step-down circuit 1. The switch control module 33 can control the turn-on voltage reduction circuit to be turned off or closed according to the input signal, that is, when the transfer signal is a voltage signal.
It should be understood that, no matter whether the first switching command is a voltage signal, a current signal, a digital signal or a computer command, the fet circuit 2 may be controlled to be turned on by the driving module 32, and a transfer signal capable of controlling the switching of the switching voltage step-down circuit 1 may be transmitted to the switching control module 33.
Referring to fig. 5, in another embodiment, the specific steps of turning off the switching step-down circuit 1 and turning on the fet circuit 2 connected in parallel to the switching step-down circuit 1 include:
s340, the detecting module 31 transmits the second switching instruction to the driving module 32 and transmits the third switching instruction to the switch control module 33.
The difference from the previous embodiment is that the detection module 31 directly transmits the third switching command to the light-on control module, rather than relaying through the driving module 32.
S350, the driving module 32 outputs a conducting signal to the fet circuit 2 based on the second switching command.
S360, the switch control module 33 outputs a turn-off signal to the switch step-down circuit 1 based on the third switching command.
S350 and S360 do not have sequential requirements for execution, and, conversely, S350 and S360 should be executed simultaneously. Further, the second switching instruction and the third switching instruction may be voltage signals, digital signals, or computer instructions.
In another embodiment, referring to fig. 6, the specific steps of turning off the switching step-down circuit 1 and turning on the fet circuit 2 connected in parallel to the switching step-down circuit 1 include:
s370, the detecting module 31 transmits a fourth switching instruction to the driving module 32.
S380, the driving module 32 outputs a turn-off signal to the switching step-down circuit 1 and outputs a turn-on signal to the fet circuit 2 based on the fourth switching instruction.
The fourth switching instruction may be a voltage signal, a digital signal, or a computer instruction. When the fourth switching command is a voltage signal, if a low-voltage signal is required as a turn-off signal and a high-voltage signal is required as a turn-on signal, the driving module 32 may be integrated with a step-down circuit and a step-up circuit. It should be understood that the driving module 32 only needs to be able to control the switch of the switching step-down circuit 1 and to control the on/off of the fet circuit 2.
The implementation principle of the voltage conversion method based on the wide voltage as the input voltage is as follows: when the input voltage is smaller than the switching voltage, the switching step-down circuit 1 is closed, and the field-effect tube circuit 2 is switched on, so that the input voltage is output after passing through the field-effect tube circuit 2. Because the resistance value of the field effect transistor circuit 2 is smaller than that of the switch voltage reduction circuit 1, the generated voltage drop is small, and the output voltage is convenient to be stabilized in the voltage range of the product requirement.
The embodiment of the application also discloses a voltage conversion device based on wide voltage of input voltage, which comprises a memory and a processor, wherein the memory stores a voltage conversion program based on wide voltage of input voltage; the processor is used for executing the steps of the voltage conversion method based on the input voltage being the wide voltage when the voltage conversion program based on the input voltage being the wide voltage is executed.
The embodiment of the application also discloses a voltage conversion circuit based on wide voltage of input voltage, refer to fig. 7, including switch buck circuit 1, field effect transistor circuit 2 and control circuit 3, the resistance value of field effect transistor circuit 2 is less than the resistance value of switch buck circuit 1.
The voltage input end of the field effect tube circuit 2 is connected with the voltage input end of the switch voltage reduction circuit 1, and the voltage output end is connected with the voltage output end of the switch voltage reduction circuit 1, namely, the field effect tube circuit 2 is connected with the switch voltage reduction circuit in parallel. The voltage input end of the control circuit 3 is connected with the voltage input end of the switch voltage reduction circuit 1, and the output end of the control circuit is respectively connected with the control end of the switch voltage reduction circuit 1 and the control end of the field effect transistor circuit 2. The output terminal of the control circuit 3 may be a voltage output terminal, or may be a signal output terminal, such as a digital signal output terminal.
The control circuit 3 is configured to obtain an input voltage, transmit a turn-off signal to the control terminal of the switching step-down circuit 1 when the input voltage is less than a preset switching voltage, and transmit a turn-on signal to the control terminal of the fet circuit 2.
It is understood that the control circuit 3 is further configured to transmit a close signal to the control terminal of the switching step-down circuit 1 and simultaneously transmit a cut-off signal to the control terminal of the fet circuit 2 when the input voltage is greater than or equal to the switching circuit.
After the control end of the switch voltage reduction circuit 1 receives a closing signal, the switch voltage reduction circuit 1 is closed; after receiving the closing signal, the switching step-down circuit 1 is closed. After the control end of the field effect transistor circuit 2 receives the conduction signal, the field effect transistor circuit 2 is conducted; upon receiving the off signal, the fet circuit 2 is turned off.
As an embodiment, referring to fig. 8, the switching buck circuit 1 includes a switching buck chip U1; the voltage input end of the switch voltage reduction chip U1 is connected with the voltage input end of the switch voltage reduction circuit 1, and the voltage output end is connected with the voltage output end of the switch voltage reduction circuit 1. The field effect transistor circuit 2 comprises a field effect transistor Q1; the drain of the field effect transistor Q1 is connected to the voltage input of the field effect transistor circuit 2, and the source is connected to the voltage output of the field effect transistor circuit 2.
The control circuit 3 includes a detection module 31, a driving module 32, and a switch control module 33. The voltage input end of the detection module 31 is connected with the voltage input end of the switch buck chip U1, and the output end is connected with the voltage input end or the signal input end of the driving module 32. The detection module 31 is configured to obtain an input voltage at a voltage input end of the switching step-down chip U1, and transmit a first switching instruction to the driving module 32 when the input voltage is less than a preset switching voltage. The detection module 31 may be a chip or a circuit with a comparison function, such as a comparator circuit.
A first voltage output end or a first signal output end of the driving module 32 is connected to the gate of the field effect transistor Q1, and a second voltage output end or a second signal output end is connected to a voltage input end or a signal input end of the switch control module 33. The driving module 32 is configured to obtain the first switching instruction transmitted by the detecting module 31, and transmit a turn-on signal to the gate of the fet Q1 and transmit a relay signal to the switch control module 33 based on the first switching instruction. The driving module 32 may be an MCU having analog-to-digital conversion or digital-to-analog conversion, or an operational amplifier circuit or a buck-boost circuit.
The voltage output end or the signal output end of the switch control module 33 is connected to the control end of the switch buck chip U1, and is configured to receive the transit signal transmitted by the driving module 32, and transmit a turn-off signal to the control end of the switch buck chip U1 based on the transit signal. The switch control module 33 may be an MCU having analog-to-digital conversion or digital-to-analog conversion, or an operational amplifier circuit or a buck-boost circuit.
As another embodiment, referring to fig. 9, the difference from the previous embodiment is that a first voltage output terminal or a first signal output terminal of the detection module 31 is connected to a voltage input terminal or a signal input terminal of the driving module 32, and a second voltage output terminal or a second signal output terminal is connected to a voltage input terminal or a signal input terminal of the switch control module 33. The detection module 31 is configured to obtain an input voltage at a voltage input end of the switching step-down chip U1, and transmit a second switching instruction to the driving module 32 and transmit a third switching instruction to the switch control module 33 when the input voltage is less than a preset switching voltage.
The driving module 32 is configured to obtain the second switching instruction transmitted by the detecting module 31, and transmit a turn-on signal to the gate of the fet Q1 based on the second switching instruction. The switch control module 33 is configured to obtain a third switching instruction transmitted by the detection module 31, and transmit a turn-off signal to the control terminal of the switching buck chip U1 based on the third switching instruction.
The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.
Claims (10)
1. A voltage conversion method based on wide voltage of input voltage is characterized by comprising the following steps:
acquiring an input voltage;
when the input voltage is smaller than the preset switching voltage, closing the switch voltage reduction circuit (1), and conducting a field effect transistor circuit (2) connected with the switch voltage reduction circuit (1) in parallel; the resistance value of the field effect transistor circuit (2) is smaller than that of the switch voltage reduction circuit (1).
2. The method according to claim 1, wherein the step of calculating the switching voltage comprises:
obtaining the fluctuation range ratio of the rated output voltage and the rated output voltage;
obtaining a switching voltage based on C = X + X Y + N;
wherein C is a switching voltage; x is rated output voltage; y is the ratio of the positive fluctuation range of the rated output voltage; n is an extension value.
3. The method according to claim 1, wherein the step of calculating the switching voltage comprises:
acquiring rated output voltage and the maximum switching duty ratio of the switching step-down circuit (1);
obtaining a switching voltage based on C = X + (X-X K) + M;
wherein C is a switching voltage; x is rated output voltage; k is the maximum switching duty ratio of the switching voltage reduction circuit (1); m is a compensation value.
4. The voltage conversion method based on the wide-width input voltage as claimed in claim 1, wherein the specific steps of turning off the switch step-down circuit (1) and turning on the fet circuit (2) connected in parallel with the switch step-down circuit (1) comprise:
the detection module (31) transmits a first switching instruction to the driving module (32);
the driving module (32) transmits a transfer signal to the switch control module (33) and outputs a conducting signal to the field effect transistor circuit (2) based on a first switching instruction;
the switch control module (33) transmits a closing signal to the switch voltage reduction circuit (1) based on the transit signal.
5. The voltage conversion method based on the wide-width input voltage as claimed in claim 1, wherein the specific steps of turning off the switch step-down circuit (1) and turning on the fet circuit (2) connected in parallel with the switch step-down circuit (1) comprise:
the detection module (31) transmits a second switching instruction to the driving module (32) and transmits a third switching instruction to the switch control module (33);
the driving module (32) outputs a conducting signal to the field effect transistor circuit (2) based on a second switching instruction;
the switch control module (33) outputs a turn-off signal to the switch voltage reduction circuit (1) based on a third switching instruction.
6. The voltage conversion method based on the wide-width input voltage as claimed in claim 1, wherein the specific steps of turning off the switch step-down circuit (1) and turning on the fet circuit (2) connected in parallel with the switch step-down circuit (1) comprise:
the detection module (31) transmits a fourth switching instruction to the driving module (32);
the driving module (32) outputs a closing signal to the switch voltage reduction circuit (1) and outputs a conducting signal to the field effect transistor circuit (2) based on a fourth switching instruction.
7. A voltage conversion device based on wide voltage of input voltage, comprising a memory and a processor, characterized in that: the memory stores a voltage conversion program based on wide voltage of input voltage; the processor is configured to perform the steps of the method of any one of claims 1-6 when running a voltage conversion program based on an input voltage being a wide voltage.
8. A voltage conversion circuit based on an input voltage is a wide voltage, includes a switching step-down circuit (1), and is characterized in that: the voltage reducing circuit also comprises a field effect transistor circuit (2) and a control circuit (3), wherein the resistance value of the field effect transistor circuit (2) is smaller than that of the switching voltage reducing circuit (1);
the voltage input end of the field effect transistor circuit (2) is connected with the voltage input end of the switch voltage reduction circuit (1), and the voltage output end of the field effect transistor circuit (2) is connected with the voltage output end of the switch voltage reduction circuit (1); the voltage input end of the control circuit (3) is connected with the voltage input end of the switch voltage reduction circuit (1), and the output end of the control circuit (3) is respectively connected with the control end of the switch voltage reduction circuit (1) and the control end of the field effect transistor circuit (2);
the control circuit (3) is used for acquiring input voltage, transmitting a closing signal to the control end of the switch voltage reduction circuit (1) when the input voltage is smaller than preset switching voltage, and transmitting a conducting signal to the control end of the field effect transistor circuit (2).
9. The voltage conversion circuit according to claim 8, wherein the input voltage is a wide voltage, and the voltage conversion circuit comprises: the switch voltage reduction circuit (1) comprises a switch voltage reduction chip U1; the voltage input end of the switch voltage reduction chip U1 is connected with the voltage input end of the switch voltage reduction circuit (1), and the voltage output end of the switch voltage reduction chip U1 is connected with the voltage output end of the switch voltage reduction circuit (1);
the field effect transistor circuit (2) comprises a field effect transistor Q1; the voltage input end of the field effect transistor Q1 is connected with the voltage input end of the field effect transistor circuit (2), and the voltage output end of the field effect transistor Q1 is connected with the voltage output end of the field effect transistor circuit (2);
the control circuit (3) comprises a detection module (31) and a driving module (32), wherein the detection module (31) is used for acquiring the input voltage of the voltage input end of the switch voltage reduction chip U1 and transmitting a first switching instruction to the driving module (32) when the input voltage is smaller than a preset switching voltage;
the driving module (32) is used for acquiring a first switching instruction transmitted by the detection module (31), and transmitting a conducting signal to the grid of the field-effect tube Q1 and a relay signal to the switch control module (33) based on the first switching instruction;
and the switch control module (33) is used for receiving the transit signal transmitted by the driving module (32) and transmitting a closing signal to the control end of the switch voltage reduction chip U1 based on the transit signal.
10. The voltage conversion circuit according to claim 8, wherein the input voltage is a wide voltage, and the voltage conversion circuit comprises: the switch voltage reduction circuit (1) comprises a switch voltage reduction chip U1; the voltage input end of the switch voltage reduction chip U1 is connected with the voltage input end of the switch voltage reduction circuit (1), and the voltage output end of the switch voltage reduction chip U1 is connected with the voltage output end of the switch voltage reduction circuit (1);
the field effect transistor circuit (2) comprises a field effect transistor Q1; the voltage input end of the field effect transistor Q1 is connected with the voltage input end of the field effect transistor circuit (2), and the voltage output end of the field effect transistor Q1 is connected with the voltage output end of the field effect transistor circuit (2);
the control circuit (3) comprises a detection module (31) and a switching control module (33), wherein the detection module (31) is used for acquiring the input voltage of the voltage input end of the switching buck chip U1, and transmitting a second switching instruction to the driving module (32) and a third switching instruction to the switching control module (33) when the input voltage is smaller than a preset switching voltage;
the driving module (32) is used for acquiring a second switching instruction transmitted by the detection module (31) and transmitting a conducting signal to the grid of the field-effect tube Q1 based on the second switching instruction;
and the switch control module (33) is used for acquiring a third switching instruction transmitted by the detection module (31) and transmitting a closing signal to the control end of the switch buck chip U1 based on the third switching instruction.
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| CN202110904707.5A CN113691129A (en) | 2021-08-07 | 2021-08-07 | Voltage conversion method, device and conversion circuit based on wide input voltage |
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| CN202110904707.5A CN113691129A (en) | 2021-08-07 | 2021-08-07 | Voltage conversion method, device and conversion circuit based on wide input voltage |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060001410A1 (en) * | 2004-07-02 | 2006-01-05 | Hiroyuki Ishikawa | Power supply apparatus using synchronous rectified step-down converter |
| US20100134078A1 (en) * | 2008-12-03 | 2010-06-03 | Maki Murakami | Step-down switching regulator |
| CN101989812A (en) * | 2009-07-31 | 2011-03-23 | 晨星软件研发(深圳)有限公司 | Direct-current (DC) power supply conversion circuit and method |
-
2021
- 2021-08-07 CN CN202110904707.5A patent/CN113691129A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060001410A1 (en) * | 2004-07-02 | 2006-01-05 | Hiroyuki Ishikawa | Power supply apparatus using synchronous rectified step-down converter |
| US20100134078A1 (en) * | 2008-12-03 | 2010-06-03 | Maki Murakami | Step-down switching regulator |
| CN101989812A (en) * | 2009-07-31 | 2011-03-23 | 晨星软件研发(深圳)有限公司 | Direct-current (DC) power supply conversion circuit and method |
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Application publication date: 20211123 |